Arthur s



(No H'odel.) j

- LYS. ATWATER.

`ELEOTEIU ABG LAMP.

No. 505,183'. Patented sept. A19, 1a9s.-

Infenor d @22am v Mainz/ay,

VUNITED STATES PATENT OEEIcE.

ARTHUR S. ATVATER, OF CLEVELAND, OHIO, ASSIGNOR TO THE ATWATER .GENERALELECTRIC COMPANY, OF SAME PLACE.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 505,183, datedSeptember 19, 1893.

Application filed January 16,l 1893. Serial No. 458,590. (No model.)

To a/ZZ whom t may concern.-

Beit known that I, ARTHUR S. ATWATEE, a citizen of the United States,and a resident of Cleveland, county of Cuyahoga, State of Chio, haveinvented certain new and useful Improvements in Arc Lamps, of which Ihereby declare the following to be a full, clear, and exact description,such as will enable others skilled in the art to which it appertains tomake and use the same.

My invention relates to improvements in arc lamps, 'and the objects areto provide a type of lamp which will be self sustaining and will requireadjustment only at very long intervals. To accomplish these results Iemploy the distinctive mechanism, and combination and arrangement of thevarious parts hereinafter described, shown in the accompanying drawings,and more specitically pointed out in the claims.

In the drawings Figure l, is a side elevation of my improved lamp. Fig.2 is a plan view of the same. Fig. 3 is an end view. Fig. t is avertical section of the dash pot, and Fig. 5 is a View of operatingmagnet.

In the drawings A is a horizontal metallic bar, mounted as a wallbracket by support a; B, is a bar similar in length to the bar A, andoscillating thereon upon the fulcrum point b which is placedconsiderably below the center line between the bars A, and B, the effectof this position being to insure a tendency of the carbon end of the barB to fall toward the bar A, when the center of gravity had beendisplaced toward that end of the bars, the lower the point of fulcrum,the greater the displacement caused thereby.

C, C', are narrow flat carbon plates clamped to the outer extremities ofthe bars A and B by thin plates C2 in such a manner as to touchthroughout their adjacent edges, when the outer ends of the bars arebrought together. Between these carbon edges is formed the arc.

In order to regulate the distance between the carbons andsecure anunvarying arc, the magnet D, is secured to the inner end of the bar A,with corresponding armatures d on the bar B. the eiect of this magnetbeing to pull down the armatures and separate the carbon edges wheneverthe edges of the carbon approach too near, so that the arc becomes tooshort and the current too strong. The electrical connections are shownin the dotted lines in Fig. 1, the current being alternating.

E andE are the binding posts. The current runs from binding post E tothe magnet D. thence along bar A to lower carbon C, thence forms the arcto upper carbon, thence runs upon the upper arm to fulcrum b which restsupon the insulated plate b and thence 6o out at post E. Both posts areinsulated as shown.

G, is a dash pot placed upon the lower bar A. and H isa plunger upon theupperbar working therein. The valve h in the plunger will be seen to beso placed that the bars will separate freely and bring the carbonstogether, but the carbons will be separated with much more difcultysince the liquid will be more slowly displaced in the downward movement7o of the piston plunger.

J and J are weather guards to preserve the fulcrum point b from raindriving under the 'cover K, omitted in Fig. 2.

It will be seen that the action of the lamp is automatic since any toogreat separation ot' the carbons weakens the current and the hold of themagnet, so that the carbons again approach until the requisite arc isformed between them. Again the arc once formed will 8o travel from endto end of the plates of carbon, as it eats its way slowly, so that along time will elapse before another adjustment will be necessary.

An additional shunt winding of tine wire X S 5 may be utilized to limitthe power of the magnet and prevent excessive magnetism when the currentis strongest. This is wound the reverse of the coarse wire Y and sotends to neutralize its effect, when the current is in 9o excess of theusual capacity of the coarse wire.

In Fig. 1 P and O represent the main and shunt circuits.

Having described my invention, what I claim as new, and desire to secureby Letters Patent, is-

1. In an arc lamp the combination of tiat carbon candle plates havinglinear edges presented to one another for the formation ot the arc, astationary holder for the lower carbon roo and an oscillating upperholder whose fulcrum point is located upon the lower holder at apointbelow the horizontal center line between said holders,substantially as described.

2. In an arc lamp, the combination of iiat carbon candles having linearedges presented to one another for the formation of the arc betweenthem, a rigid lower carbon holder, an oscillating upper carbon holderand means for adjusting the relative positions of the upper and lowercarbon plates, consisting in the electro-magnet D, upon the lowerholder, and armature orarmatures upon the upper holder, substantially asdescribed.

3. In an arc lamp, provided with flat carbon plate candles, thecombination of a lower fixed carbon holder, an upper oscillating holder,and means for regulating the length of the arc between the plates,consisting in the magnet D on the lamp circuit, located upon one of theholders, and armatures upon the other holder, with a modifying shuntcoil upon the magnet reversely wound to the main circuit, substantiallyas described.

4. In an arc lamp provided with plate carbon candles having linear edgespresented to one another for the formation of an arc, the combination ofa fixed lower holder', and oscillating upper holder, with means forcontrolling the movement of the upper holder and length of the arcconsisting in the electro-magnet D upon the lamp circuit placed on thelower holder, one or more armatures upon the upper holder, and a dashpotbetween said holders whereby an easy movement is given the oscillatingarm in bringing the cai-bons together, but a difficult movement insepar- 35 ating them.

ARTHUR S. ATWATER. lVitnesses:

WAI. M. MONROE, .Toi-IN T. LIsTER.

